Quote:
Originally Posted by gainreduction  I'm not a tech so be easy on me if this is a stupid question.
I'm about to re-cap my console and wondering if there are other kinds of caps that can be used instead of electrolytics which have a limited lifespan and a bad reputation.
Or is quality electrolytics (been recommended Panasonic and rubycon) the only way to go ?
thanx. |
As has already been noted, the size of equivalent film capacitors is prohibitive, especially in the context of consoles that are often pretty tight pcb layouts.
IMO the bad reputation of elctrolytics is underserved when properly used. In consoles they are typically used for DC blocking so as long as the LF pole is set arbitrarily low and they are working into relatively high impedances they will be pretty accurate.
You may want to pay attention to ESR/ESL in circuits where they are called on to do more work, like in the gain leg of a mic preamp where the working impedance at high gains may be relatively low to keep preamp noise down.
Another characteristic you might want to pay attention to is in the mic preamp front ends where they are often called on to block phantom voltage. The leakage characteristic of some of the newer minaturized electrolytics may cause audible noise (this is difficult to parse out from cap data sheets since it's not the amount but character of the leakage that matters. You might want to try a few samples first or listen to specific advice from others who have experience with a given cap series in that application).
The main place where their bad reputation is deserved is in cheap speaker crossovers where they are operating at higher currents and can have significant, varying terminal voltages in the heart of the audio band where we are more likely to hear any non-ideal artifacts generated.
Have fun and do no harm.
JR